Monday, April 28, 2008

7.32 Nutritional glaucoma

The above is Mexican poppy (botanically: Argemone mexicana) or Satyanashi. Its seeds give out a poisonous oil, the argemone oil (aka the katkar oil), which is indistinguishable from dark mustard oil.

In northern India, mustard oil is used for cooking. If some unscrupulous merchants were to adulter mustard oil with argemone oil, then an epidemic poisoning would ensue (known as Epidemic Dropsy). In fact, the first case was reported in Bombay in 1877. And more recently in Delhi in 1998 when 2,552 cases were reported and 65 died.

Sanguinarine, one of the 2 alkaloids found in argemone oil causes dilation of blood vessels/capillaries. The patients suffer general edema (i.e., dropsy) owing to leakage of plasma into the surrounding tissues. This leakage also involves the blood vessels of the uvea, thereby hindering the uveal outflow. As a result, a special form of glaucoma develops, which persists even after the poison is excluded that often requires medical/surgical intervention.

Fortunately, Epidemic Dropsy is largely a thing of the past. However, nutritional glaucoma can appear in a totally unexpected manner. In a recent case reported in Taiwan (March, 2008), a 40-year-old lady developed blurred vision with high IOP (30mmHg) - after a one-root-per-day consumption of ginseng for one month. Medicinal ginseng is quite expensive, in fact, not everyone can afford such a regimen. So, there is no epidemic here. It was speculated that high-dose ginseng might have altered the viscosity of the aqueous humor causing a sluggish outflow.

(Korean ginseng, the ones with the highest quality - the"天字第一號 (Heaven No 1)" - can fetch USD10,000 per root.)

After the ginseng runs its cause, recovery, most likely total, is expected for this particular patient. Follow-ups are of course recommended.

Sometimes the eye doctors must connect the dots and become a capable medical sleuth.